全文获取类型
收费全文 | 451篇 |
免费 | 17篇 |
国内免费 | 12篇 |
专业分类
安全科学 | 15篇 |
废物处理 | 8篇 |
环保管理 | 94篇 |
综合类 | 73篇 |
基础理论 | 115篇 |
环境理论 | 1篇 |
污染及防治 | 109篇 |
评价与监测 | 26篇 |
社会与环境 | 34篇 |
灾害及防治 | 5篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 13篇 |
2021年 | 12篇 |
2020年 | 7篇 |
2019年 | 8篇 |
2018年 | 21篇 |
2017年 | 22篇 |
2016年 | 29篇 |
2015年 | 24篇 |
2014年 | 22篇 |
2013年 | 43篇 |
2012年 | 29篇 |
2011年 | 44篇 |
2010年 | 19篇 |
2009年 | 17篇 |
2008年 | 26篇 |
2007年 | 17篇 |
2006年 | 16篇 |
2005年 | 13篇 |
2004年 | 13篇 |
2003年 | 13篇 |
2002年 | 12篇 |
2001年 | 11篇 |
2000年 | 2篇 |
1999年 | 5篇 |
1998年 | 2篇 |
1996年 | 2篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1966年 | 1篇 |
1963年 | 2篇 |
1942年 | 1篇 |
排序方式: 共有480条查询结果,搜索用时 15 毫秒
131.
Benjamin J. Crain Chad Stachowiak Patrick F. McKenzie James N. Sanchirico Kailin Kroetz Paul R. Armsworth 《Ambio》2021,50(6):1237
Open space areas protected by local communities may augment larger scale preservation efforts and may offer overlooked benefits to biodiversity conservation provided they are in suitable ecological condition. We examine protected areas established by local communities through ballot initiatives, a form of direct democracy, in California, USA. We compare ecological conditions of wooded habitats on local ballot protected sites and on sites protected by a state-level conservation agency. Collectively, we found few differences in ecological conditions on each protected area type. Ballot sites had greater invasive understory cover and larger trees. Community dissimilarity patterns suggested ballot sites protect a complementary set of tree species to those on state lands. Overall, geographic characteristics influenced onsite conditions more than details of how sites were protected. Thus, community-driven conservation efforts contribute to protected area networks by augmenting protection of some species while providing at least some protection to others that might otherwise be missed.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01469-8) contains supplementary material, which is available to authorized users. 相似文献
132.
Animals face trade-offs between predation risk and foraging success depending on their location in the landscape; for example, individuals that remain near a common shelter may be safe from predation but incur stronger competition for resources. Despite a long tradition of theoretical exploration of the relationships among foraging success, conspecific competition, predation risk, and population distribution in a heterogeneous environment, the scenario we describe here has not been explored theoretically. We construct a model of habitat use rules to predict the distribution of a local population (prey sharing a common shelter and foraging across surrounding habitats). Our model describes realized habitat quality as a ratio of density- and location-dependent mortality to density-dependent growth. We explore how the prey distribution around a shelter is expected to change as the parameters governing the strength of density dependence, landscape characteristics, and local abundance vary. Within the range of parameters where prey spend some time away from shelter but remain site-attached, the prey density decreases away from shelter. As the distance at which prey react to predators increases, the population range generally increases. At intermediate reaction distances, however, increases in the reaction distance lead to decreases in the maximum foraging distance because of increased evenness in the population distribution. As total abundance increases, the population range increases, average population density increases, and realized quality decreases. The magnitude of these changes differs in, for example, ‘high-’ and ‘low-visibility’ landscapes where prey can detect predators at different distances. 相似文献
133.
James?C.?MakinsonEmail author Benjamin?P.?Oldroyd Timothy?M.?Schaerf Wandee?Wattanachaiyingcharoen Madeleine?Beekman 《Behavioral ecology and sociobiology》2011,65(5):945-958
The Red Dwarf honeybee (Apis florea) is one of two basal species in the genus Apis. A. florea differs from the well-studied Western Hive bee (Apis mellifera) in that it nests in the open rather than in cavities. This fundamental difference in nesting biology is likely to have implications
for nest-site selection, the process by which a reproductive swarm selects a new site to live in. In A. mellifera, workers show a series of characteristic behaviors that allow the swarm to select the best nest site possible. Here, we describe
the behavior of individual A. florea workers during the process of nest-site selection and show that it differs from that seen in A. mellifera. We analyzed a total of 1,459 waggle dances performed by 197 scouts in five separate swarms. Our results suggest that two
fundamental aspects of the behavior of A. mellifera scouts—the process of dance decay and the process of repeated nest site evaluation—do not occur in A. florea. We also found that the piping signal used by A. mellifera scouts to signal that a quorum has been reached at the chosen site, is performed by both dancing and non-dancing bees in
A. florea. Thus, the piping signal appears to serve a different purpose in A. florea. Our results illustrate how differences in nesting biology affect the behavior of individual bees during the nest-site selection
process. 相似文献
134.
We argue that attempts to extrapolate moral motives for non‐egoistic behavior in organizational behavior often interpret results empathically or deontically, while leaving other moral motivational frames, such as the utilitarian and virtue ethical, under‐examined. We encourage the creation of experimental measures to distinguish various philosophical frames. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
135.
Aaron S. Veenstra Benjamin A. Lyons Amy Fowler-Dawson 《Environmental Communication: A Journal of Nature and Culture》2016,10(3):322-336
ABSTRACTAlthough recent expansions in hydraulic fracking operations across the United States have led to greater news coverage and attention from the public, overall understanding remains fairly low. For some, relevant social identities, including environmental or political, may provide a short cut to becoming informed about fracking, or to determining what they believe about it and how that influences their positions on fracking policies. Social identity influence frameworks provide an approach to understanding the relationships between belief and identity, which this study investigates through its affiliational and attitudinal components. National survey data are used to model pathways from environmental and political identities to beliefs about risks associated with fracking. Environmental attitudes significantly predicted belief that fracking has health risks, and mediated a relationship from environmental group affiliation, but environmental information was not significant. Ideology had direct and indirect effects, through partisan media use, while partisanship had direct effects on beliefs about environmental risks. 相似文献
136.
Christopher Kuzdas Benjamin P. Warner Arnim Wiek Raffaele Vignola Mariel Yglesias Daniel L. Childers 《Sustainability Science》2016,11(2):231-247
Many new forms of water governance are emerging in response to economic and social needs and wants, as well as water-related problems such as scarcity, injustice, and conflict. However, there is little evidence on how sustainable these governance regimes are, which would be critical for making progress toward sustainable and just water governance. In this article, we present the results of a transdisciplinary multi-criteria sustainability assessment of alternative governance regimes for Guanacaste Province, Costa Rica. The assessment specifies differences between sustainable and unsustainable governance regimes, while also pinpointing how the current water governance regime performs in comparison to those alternatives. The findings indicate that those governance regimes with just and deliberative stakeholder involvement, secure groundwater reserves, and healthy dry tropical ecosystems were considered sustainable and just. In contrast, the current state of water governance was found to be at high risk of digressing toward unsustainable systems where rural communities lack rights and influence, where economies favor agro-industry and high impact tourism at the expense of rural livelihoods, and where water scarcity overwhelms weak governance. This assessment study clarifies water sustainability goals, asserts the need for transformational change, and offers a pragmatic foundation for actions toward sustainable water governance. 相似文献
137.
Evaluation of Progress in Achieving TMDL Mandated Nitrogen Reductions in the Neuse River Basin, North Carolina 总被引:2,自引:0,他引:2
Management efforts to control excess algal growth in the Neuse River and Estuary, North Carolina began in the 1980s, with
an initial focus on phosphorus (P) input reduction. However, continued water quality problems in the 1990s led to development
of a Total Maximum Daily Load (TMDL) for nitrogen (N) in 1999 to improve conditions in N-sensitive estuarine waters. Evaluation
of the effectiveness of management actions implemented in the Neuse River basin is a challenging endeavor due to natural variations
in N export associated with climate. A simplified approach is presented that allows evaluation of trends in flow-normalized
nutrient loading to provide feedback on effectiveness of implemented actions to reduce N loading to estuarine waters. The
approach is applied to five watershed locations, including the headwaters of the Neuse Estuary. Decreases in nitrate + nitrite
(NO3–N) concentrations occurred throughout the basin and were largest just downstream of the Raleigh metropolitan area. Conversely,
concentrations of total Kjeldahl N (TKN) increased at many stations, particularly under high flow conditions. This indicates
a relative increase in organic N (Org-N) inputs since the mid-1990s. Overall, patterns in different N fractions at watershed
stations indicate both partial success in reducing N inputs and ongoing challenges for N loading under high flow conditions.
In downstream waters, NO3–N concentrations decreased concurrent with TMDL implementation in the upper portion of the estuary but not in the middle
and lower reaches. The lack of progress in the middle and lower reaches of the estuary may, at least in part, be affected
by remineralization of settled particle-bound N deposited under high river flows. 相似文献
138.
139.
Influence of organic waste and residue mud additions on chemical,physical and microbial properties of bauxite residue sand 总被引:1,自引:0,他引:1
Benjamin E. H. Jones Richard J. Haynes Ian R. Phillips 《Environmental science and pollution research international》2011,18(2):199-211
Background, aim and scope
In an alumina refinery, bauxite ore is treated with sodium hydroxide at high temperatures and pressures and for every tonne of alumina produced, about 2 tonnes of alkaline, saline bauxite processing waste is also produced. At Alcoa, a dry stacking system of disposal is used, and it is the sand fraction of the processing waste that is rehabilitated. There is little information available regarding the most appropriate amendments to add to the processing sand to aid in revegetation. The purpose of this study was to investigate how the addition of organic wastes (biosolids and poultry manure), in the presence or absence of added residue mud, would affect the properties of the residue sand and its suitability for revegetation. 相似文献140.
James S. Heslin Benjamin F. Hobbs 《Journal of the Air & Waste Management Association (1995)》2013,63(7):956-966
A new approach for state- and utility-level analysis of the cost and regional economic impacts of strategies for reducing utility SO2 emissions is summarized and applied to Ohio. The methodology is based upon probabilistic production costing and economic input-output analysis. It is an improvement over previous approaches because it: (1) accurately models random outages of generating units, “must-run” constraints on unit output, and the distribution of power demands; and (2) runs quickly on a microcomputer and yet considers the entire range of potential control strategies from a systems perspective. The input-output analysis considers not only the economic effects of utility fuel use and capital investment, but also those of increased electric rates. Two distinct strategies are found to be most attractive for Ohio. The first, more flexible one, consists of emissions dispatching (ED) alone to meet short run emissions reduction targets. A 75 percent reduction can then be achieved by the turn of the century by combining ED and fuel switching (FS) with flue gas desulfiirization, limestone Injection multistage burners, and physical coal cleaning at selected plants. The second is a scrubber-based strategy which includes ED. By the year 2000, energy conservation becomes a cost effective component of these strategies. In order to minimize compliance costs, acid rain legislation which facilitates emissions trading and places regional tonnage limits on emissions is desirable. 相似文献